Over the years, various techniques and devices have been developed to help a person accurately aim a firearm, such as a rifle or a target pistol. One common approach is to mount a sight or scope on the firearm's barrel. A person then uses the sight or scope to view an intended target in association with a reticle, often with a degree of magnification. Although existing firearm sights of this type have been generally adequate for their intended purposes, they have not been satisfactory in all respects.
For example, some pre-existing sights have included the capability to record an image showing a target and/or a reticle, and to later display one or more of these recorded images. However, when these recorded images are displayed, it is possible for a safety hazard to occur. For example, if the recorded image is presented on an electronic display that is separately used to show actual targets, a user may mistake the recorded image for an actual target, and may then discharge the weapon in the belief that he or she is shooting at something in the recorded image, when the weapon is actually pointed at some other person or thing. Moreover, even if the user does not intentionally discharge the weapon while viewing recorded images, there is always a risk of accidental discharge. Consequently, if the user is distracted while viewing recorded images, or gives the weapon and sight to another person who is distracted or who is not familiar with weapon safety, the weapon may be inadvertently pointed in a direction that presents a safety hazard.
A different consideration is that hunting regulations in most states stipulate that hunting is allowed only during the time from one-half hour before sunrise to one-half hour after sunset. The intent of these regulations is to prevent the unsafe practice of shooting in very low light levels, where the actual identity of a target may be questionable. The level of illumination at one-half hour before sunrise and at one-half hour after sunset is sometimes referred to as “civil twilight”, and falls in a luminance range of 0.1 to 1.0 foot-candles. This luminance range corresponds to a cloudless sky. Other conditions can cause the illumination level to drop below that of civil twilight at almost any time during the day, for example where there is a dense cloud cover, or where a hunter is in a dense forest. There is no easy way for hunters and game wardens to determine actual levels of illumination, and this is why states have adopted the compromise approach of defining allowable hunting conditions in terms of dusk and dawn, rather than in terms of actual levels of illumination. Existing sights provide hunters with no assistance in detecting or avoiding actual low light conditions that can present potential safety hazards.
Still another consideration is that virtually all states have a hunting regulation that requires hunters to wear a fluorescent orange garment above the waist while hunting. This color does not occur naturally in any big game animals, or in their environment. The fluorescent orange color is thus intended to be a visual cue to a hunter that a person is present, rather than a potential animal target. Even where such a garment is present, the patch of orange color may be partly obscured by other objects in the scene, or may be very small if the hunter is a significant distance from the person wearing the garment. In either case, the presence of the orange color in the scene may be inadvertently and unintentionally overlooked by a hunter, resulting in a potentially dangerous situation for the person wearing the garment. Existing rifle sights provide hunters with no assistance in detecting fluorescent orange to avoid potentially dangerous hunting situations.